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Question
How does the resolving power of a microscope change when
(i) the diameter of the objective lens is decreased?
(ii) the wavelength of the incident light is increased ?
Justify your answer in each case.
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Solution
The resolving power of a microscope is given by the relation
`"RP" = 1/d_"min" = (2"n" sin beta)/(1.22 lambda)`
(i) When the diameter of the objective lens is decreased β decreases so resolving power decreases.
(ii) When the wavelength of the incident light is increased resolving power decreases.
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